Since the disputed election last June, Ahmadinejad's government has sought different ways to further crack down on the internet in Iran. Now, access to almost all reformist websites is blocked, including those of the reformist candidates, Mir Hossein Mousavi and Mehdi Karoubi.

Last week Iran launched a national webmail service via iran.ir, intended to replace free foreign webmail services with a domestic one that is easier to control. All government employees are being urged to use it instead of foreign webmail providers. According to the Iranian official figures, 95% of Iranians currently use Yahoo Mail, Gmail and Hotmail accounts.

Human rights activists in Iran fear that the national webmail service is part of a bigger plan to localise the internet within Iran's borders although many believe it is too late for Iran to do so effectively.

Recently, officials have blocked access to Google Translate, which has provided English to Persian, Persian to English service since June. But, as has happened in China, is filtering Google the next step?

Although iran.ir does not yet have the capacity to provide free webmail services for everyone, it will do so shortly. Gmail is reportedly blocked in some parts of Iran and its audio and video attachments are impossible to download. At least 5m websites are filtered in Iran, but for clever users, filtering is pointless; thousands of proxy sites distribute the net's wider content to blogs or email addresses. But even these users have so far been unable to bypass the block on Gmail attachments.

You might think that this is only going to inconvenience a few people, but you would be wrong: Iran has nearly a million bloggers, around 10% of whom are active. Iran's native language is also among the top 10 languages used online. The power of the internet in Iran became clear for the world when Iranian protesters used social networking websites such as Facebook and Twitter to cover up the media absence in Iran since June. Journalists have been banned from reporting demonstrations since then.

The internet has been a nightmare for Ahmadinejad since he took office the first time in 2005. His government jailed some bloggers and when he was criticised, largely by Iran's huge blogging community, the authorities established samandehi.ir in 2007. This was a site where all bloggers were required to register with the government and provide personal information, including usernames and passwords – otherwise it would be blocked. This led to an outcry among many Iranians who consider the net an independent and free forum for expression. Many protested by publishing "I will not register my blog" banners in their blogs.

Samandehi.ir became impractical in reality and the government didn't take it seriously, but thousands of blogs have been banned since then. Last March, just a couple of months before the presidential election, Omid Mir Sayafi, a 29-year-old blogger, committed suicide in the notorious Evin prison in Tehran. He had been sentenced to 30 months for insulting Iran's supreme leader in his blog.

But the internet made Ahmadinejad's government angrier when users in Iran spread news of the fraudulent presidential election. Mir Hossein Mousavi asked his supporters to act as an individual media in the absence of free media. Since then Iranian protesters have used the internet to organise demonstrations and exchange information.

Meanwhile, the Iranian government tried to police the internet months after the election and for a while stopped people at the airport to check if they were on Facebook. Many have been imprisoned and sentenced since June in Iran on the basis of their Facebook and Twitter profiles.

Despite all this intimidation, protesters in Iran are enormously active on the internet. The 31st anniversary of the Islamic Revolution is coming on February 11, and protesters are again organising to exploit the occasion. In the past few days, Iran has partially cut off the internet in different areas of Iran and activists fear that it might be cut off completely on 11 February.

Whether Ahmadinejad succeeds or not, it seems that he is not only adopting China as a model for Iran's political future, but as a model for the future of Iran's online community.